package 二叉树相关问题;

public class 二叉树的最近公共祖先 {

    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
        if(root == null)
            return null;

        if(p == root || q == root)
            return root;

        TreeNode left = lowestCommonAncestor(root.left,p,q);
        TreeNode right = lowestCommonAncestor(root.right,p,q);

        if(left != null && right != null)
            return root;
        return left == null ? right : left;
    }
}
